////
This guide is maintained in the main Quarkus repository
and pull requests should be submitted there:
https://github.com/quarkusio/quarkus/tree/master/docs/src/main/asciidoc
////
= Quarkus - Working with HashiCorp Vault

include::./attributes.adoc[]
:config-file: application.properties
:vault-version: 1.2.2
:root-token: s.5VUS8pte13RqekCB2fmMT3u2
:client-token: s.s93BVzJPzBiIGuYJHBTkG8Uw

https://www.vaultproject.io/[HashiCorp Vault] is a multi-purpose tool aiming at protecting sensitive data, such as
credentials, certificates, access tokens, encryption keys, ... In the context of Quarkus,
it is being used for 3 primary use cases:

* mounting a map of properties stored into the
https://www.vaultproject.io/docs/secrets/kv/index.html[Vault kv secret engine] as an Eclipse MicroProfile config source
* fetch credentials from Vault when configuring an Agroal datasource
* access the Vault _kv secret engine_ programmatically

Under the hood, the Quarkus Vault extension takes care of authentication when negotiating a client Vault token plus
any transparent token or lease renewals according to ttl and max-ttl.

== Prerequisites

To complete this guide, you need:

* roughly 20 minutes
* an IDE
* JDK 1.8+ installed with `JAVA_HOME` configured appropriately
* Apache Maven 3.5.3+
* Docker installed

== Starting Vault

Let's start Vault in development mode:

[source, shell, subs=attributes+]
----
docker run --rm --cap-add=IPC_LOCK -e VAULT_ADDR=http://localhost:8200 -p 8200:8200 -d --name=dev-vault vault:{vault-version}
----

You can check that vault is running with:
[source, shell, subs=attributes+]
----
docker logs dev-vault
----

You should see:

[source, shell, subs=attributes+]
----
==> Vault server configuration:

             Api Address: http://0.0.0.0:8200
                     Cgo: disabled
         Cluster Address: https://0.0.0.0:8201
              Listener 1: tcp (addr: "0.0.0.0:8200", cluster address: "0.0.0.0:8201", max_request_duration: "1m30s", max_request_size: "33554432", tls: "disabled")
               Log Level: info
                   Mlock: supported: true, enabled: false
                 Storage: inmem
                 Version: Vault v{vault-version}

WARNING! dev mode is enabled! In this mode, Vault runs entirely in-memory
and starts unsealed with a single unseal key. The root token is already
authenticated to the CLI, so you can immediately begin using Vault.

You may need to set the following environment variable:

    $ export VAULT_ADDR='http://0.0.0.0:8200'

The unseal key and root token are displayed below in case you want to
seal/unseal the Vault or re-authenticate.

Unseal Key: 0lZ2/vzpa92pH8gersSn2h9b5tmzd4m5sqIdMC/4PDs=
Root Token: {root-token}

Development mode should NOT be used in production installations!

==> Vault server started! Log data will stream in below:
----

In development mode, Vault gets configured with several options that makes it convenient:

* Vault is already initialized with one key share (whereas in normal mode this has to be done explicitly and the
number of key shares is 5 by default)
* the unseal key and the root token are displayed in the logs (please write down the root token, we will need it
in the following step)
* Vault is unsealed
* in-memory storage
* TLS is disabled
* a _kv secret engine v2_ is mounted at `secret/`

In the following step, we are going to add a `userpass` authentication that we will use from the Quarkus application,
to access a secret stored in the _kv secret engine_.

First open a shell inside the vault container:

[source, shell, subs=attributes+]
----
docker exec -it dev-vault sh
----

Set the `VAULT_TOKEN` with the value that was printed in the logs:

[source, shell, subs=attributes+]
----
export VAULT_TOKEN={root-token}
----

You can check Vault's status using the CLI command `vault status`:

[source, shell]
----
Key             Value
---             -----
Seal Type       shamir
Initialized     true
Sealed          false
Total Shares    1
Threshold       1
Version         1.2.2
Cluster Name    vault-cluster-b07e80d8
Cluster ID      55bd74b6-eaaf-3862-f7ce-3473ab86c57f
HA Enabled      false
----

For simplicity reasons, we are going to use a _kv secret engine version 1_ (which is the default) mounted at path
`secret` instead of the pre-configured _kv version 2_ available in dev mode. So let's disable the current kv engine,
and recreate a new one:

[source, shell]
----
# this will disable the current kv version 2 secret engine mounted at path 'secret'
vault secrets disable secret

# this will enable a new kv engine version 1 at path 'secret'
vault secrets enable -path=secret kv
----

Now let's add a secret configuration for our application:

[source, shell]
----
vault kv put secret/myapps/vault-quickstart/config a-private-key=123456
----

We have defined a path `secret/myapps/vault-quickstart` in Vault that we need to give access to from the Quarkus application.

Create a policy that gives read access to `secret/myapps/vault-quickstart` and subpaths:

[source, shell]
----
cat <<EOF | vault policy write vault-quickstart-policy -
path "secret/myapps/vault-quickstart/*" {
  capabilities = ["read"]
}
EOF
----

[NOTE]
====
When using a _kv secret engine version 2_, secrets are written and fetched at path `<mount>/*data*/<secret-path>`
as opposed to `<mount>/<secret-path>` in a _kv secret engine version 1_.
It does not change any of the CLI commands (i.e. you do not specify `data` in your path).
However it does change the policies, since capabilities are applied to the real path. In the example above,
the path should be `secret/*data*/myapps/vault-quickstart/*` if you were working with a _kv secret engine version 2_.
====

And finally, let's enable the _userpass auth secret engine_, and create user `bob` with access to the `vault-quickstart-policy`:

[source, shell]
----
vault auth enable userpass
vault write auth/userpass/users/bob password=sinclair policies=vault-quickstart-policy
----

[NOTE]
====
The Vault extension also supports alternate authentication methods such as:

 - https://www.vaultproject.io/docs/auth/approle.html[approle]
 - https://www.vaultproject.io/docs/auth/kubernetes.html[kubernetes] when deploying the Quarkus application
and Vault into Kubernetes

It is also possible to directly pass a `quarkus.vault.authentication.client-token`, which will bypass the authentication process.
This could be handy in development where revocation and ttl are not a concern.

Check the extension configuration documentation for more information.
====

To check that the configuration is correct, try logging in:

[source, shell]
----
vault login -method=userpass username=bob password=sinclair
----

You should see:

[source, shell, subs=attributes+]
----
Success! You are now authenticated. The token information displayed below
is already stored in the token helper. You do NOT need to run "vault login"
again. Future Vault requests will automatically use this token.

Key                    Value
---                    -----
token                  {client-token}
token_accessor         OKNipTAgxWbxsrjixASNiwdY
token_duration         768h
token_renewable        true
token_policies         ["default" "vault-quickstart-policy"]
identity_policies      []
policies               ["default" "vault-quickstart-policy"]
token_meta_username    bob
----

Now set `VAULT_TOKEN` to the `token` above (instead of the root token), and try reading the vault-quickstart secret config:

[source, shell, subs=attributes+]
----
export VAULT_TOKEN={client-token}
vault kv get secret/myapps/vault-quickstart/config
----

You should see:

[source, shell]
----
======== Data ========
Key              Value
---              -----
a-private-key    123456
----

== Create a quarkus application with a secret configuration

[source, subs=attributes+]
----
mvn io.quarkus:quarkus-maven-plugin:{quarkus-version}:create \
    -DprojectGroupId=org.acme \
    -DprojectArtifactId=vault-quickstart \
    -DclassName="org.acme.quickstart.GreetingResource" \
    -Dpath="/hello" \
    -Dextensions="vault,hibernate-orm,jdbc-postgresql"
cd vault-quickstart
----

Configure access to vault from the `{config-file}`:

[source,properties]
----
# vault url
quarkus.vault.url=http://localhost:8200

# vault authentication
quarkus.vault.authentication.userpass.username=bob
quarkus.vault.authentication.userpass.password=sinclair

# path within the kv secret engine where is located the vault-quickstart secret configuration
quarkus.vault.secret-config-kv-path=myapps/vault-quickstart/config
----

This should mount whatever keys are stored in `secret/myapps/vault-quickstart` as MicroProfile config properties.

Let's verify that by adding a new endpoint in GreetingResource:

[source,java]
----
@Path("/hello")
public class GreetingResource {

    @ConfigProperty(name = "a-private-key")
    String privateKey;

    ...

    @GET
    @Path("/private-key")
    @Produces(MediaType.TEXT_PLAIN)
    public String privateKey() {
        return privateKey;
    }
}
----

Now compile the application and run it:

[source,shell]
----
./mvnw clean install
java -jar target/vault-quickstart-1.0-SNAPSHOT-runner.jar
----

Finally test the new endpoint:

[source,shell]
----
curl http://localhost:8080/hello/private-key
----

You should see:

[source,shell]
----
123456
----

== Fetching credentials from Vault with Hibernate ORM

Start a PostgreSQL database:

[source,shell]
----
docker run --ulimit memlock=-1:-1 -it --rm=true --memory-swappiness=0 --name postgres-quarkus-hibernate -e POSTGRES_USER=sarah -e POSTGRES_PASSWORD=connor -e POSTGRES_DB=mydatabase -p 5432:5432 postgres:10.5
----

Create a simple service:

[source,java]
----
@ApplicationScoped
public class SantaClausService {

    @Inject
    EntityManager em;

    @Transactional
    public List<Gift> getGifts() {
        return (List<Gift>) em.createQuery("select g from Gift g").getResultList();
    }
}
----

With its `Gift` entity:

[source,java]
----
@Entity
public class Gift {

    private Long id;
    private String name;

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator="giftSeq")
    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}
----

Finally, add a new endpoint in `GreetingResource`:

[source,java]
----
@Inject
SantaClausService santaClausService;

@GET
@Path("/gift-count")
@Produces(MediaType.TEXT_PLAIN)
public int geGiftCount() {
    return santaClausService.getGifts().size();
}
----

Create a new path in Vault where the database password will be added:

[source,shell]
----
# set the root token again
export VAULT_TOKEN={root-token}
vault kv put secret/myapps/vault-quickstart/db password=connor
----

Since we allowed read access on `secret/myapps/vault-quickstart/` subpaths in the policy, there is nothing else
we have to do to allow the application to read it.

When fetching credentials from Vault that are intended to be used by the Agroal connection pool, we need
first to create a named Vault credentials provider in the {config-file}:

[source,properties]
----
quarkus.vault.credentials-provider.mydatabase.kv-path=myapps/vault-quickstart/db
----

This defines a credentials provider `mydatabase` that will fetch the password from key `password`
at path `myapps/vault-quickstart/db`.

The credentials provider can now be used in the datasource configuration, in place of the `password`
property:

[source,properties]
----
# configure your datasource
quarkus.datasource.url = jdbc:postgresql://localhost:5432/mydatabase
quarkus.datasource.driver = org.postgresql.Driver
quarkus.datasource.username = sarah
#quarkus.datasource.password = connor
quarkus.datasource.credentials-provider = mydatabase

# drop and create the database at startup (use `update` to only update the schema)
quarkus.hibernate-orm.database.generation=drop-and-create
----

Restart the application after rebuilding it, and test it with the new endpoint:

[source,shell]
----
curl http://localhost:8080/hello/gift-count
----

You should see:

[source,shell]
----
0
----

[NOTE]
====
The Vault extension also supports using https://www.vaultproject.io/docs/secrets/databases/index.html[dynamic database credentials]
through the `database-credentials-role` property on the `credentials-provider`. The Vault setup is more
involved and goes beyond the scope of that quickstart guide.
====

== Programmatic access to the KV secret engine

Sometimes secrets are retrieved from an arbitrary path that is known only at runtime through an application
specific property, or a method argument for instance.
In that case it is possible to inject a Quarkus VaultKVSecretEngine, and retrieve secrets programmatically.

For instance, in `GreetingResource`, add:

[source,java]
----
@Inject
VaultKVSecretEngine kvSecretEngine;

...

@GET
@Path("/secrets/{vault-path}")
@Produces(MediaType.TEXT_PLAIN)
public String getSecrets(@PathParam("vault-path") String vaultPath) {
    return kvSecretEngine.readSecret("myapps/vault-quickstart/" + vaultPath).toString();
}
----

Restart the application after rebuilding it, and test it with the new endpoint:

[source,shell]
----
curl http://localhost:8080/hello/secrets/db
----

You should see:
[source,shell]
----
{password=connor}
----

== TLS

In production mode, TLS should be activated between the Quarkus application and Vault to prevent _man-in-the-middle_ attacks.

There are several ways to configure the Quarkus application:

* through the standard `javax.net.ssl.trustStore` system property, which should refer to a JKS truststore containing
the trusted certificates
* using property `quarkus.vault.tls.ca-cert`, which should refer to a pem encoded file.

If `quarkus.vault.tls.ca-cert` is not set and the Quarkus application is using the Kubernetes authentication,
TLS will be active and use the CA certificate bundle located in `/var/run/secrets/kubernetes.io/serviceaccount/ca.crt`.
If you want to disable this behavior (for instance when using a trust store), you need to set it explicitly using:
`quarkus.vault.tls.use-kubernetes-ca-cert=false`.

The last relevant property is `quarkus.vault.tls.skip-verify`, which allows to communicate with Vault using TLS,
but without checking the certificate authenticity. This may be convenient in development, but is strongly
discouraged in production as it is not more secure than talking to Vault in plain HTTP.

== Conclusion

As a general matter, you should consider reading the extensive https://www.vaultproject.io/docs/[Vault documentation]
and apply best practices.

The features exposed today through the Vault extension covers only a small fraction of what the product is capable of.
Still, it addresses already some of the most common microservices scenarii (e.g. sensitive configuration and database
credentials), which goes a long way towards creating secured applications.

[[configuration-reference]]
== Configuration Reference

include::{generated-dir}/config/quarkus-vault.adoc[opts=optional, leveloffset=+1]